Some automotive vehicles conventionally utilize hollow, tubular drive or propeller shafts for transmitting driving torque from the engine to the driving wheels. It is not uncommon for such a shaft to be subjected to vibrations from one or more sources. It is desirable to damp such vibrations so as to provide a quieter and smoother ride.
Most of the propeller shafts in use heretofore have been of uniform diameter from one end to the other. Recently, however, some drive shafts have at least one end which is smaller in diameter than the remainder of the shaft. A shaft having such smaller diameter at either or both of its ends has certain advantages, such as enabling the use of smaller universal joints than otherwise would be possible, as well as minimizing the space and weight of the parts required to couple the shaft to the universal joints.
It has been common heretofore simply to slide a substantially cylindrical damper into a hollow drive shaft from one end thereof, the damper being made of materials which damp the vibrations and attenuate noise. Typical examples of such dampers are disclosed in U.S. Pat. Nos. 2,751,765; 3,075,406; 4,014,184; and 4,909,361, the disclosures of which are incorporated herein by reference.
A damper especially adapted for use in conjunction with a propeller shaft having reduced diameter ends is disclosed in copending application Ser. No. 08/779,789 filed Jan. 7, 1997. Such damper can be inserted in a propeller shaft even after the ends of the latter have been reduced in diameter, thereby enabling the damper to be assembled with the drive shaft at any time before the drive shaft is coupled to the vehicle's drive train. In some instances, however, it may be preferred to assemble a damper with a drive shaft before the ends thereof are reduced. This will require that the damper be assembled with the drive shaft by the shaft manufacturer as one of the operating steps in producing the shaft.